Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.3 (collagenase)
 18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Purified collagenase of Clostridium histolyticum was shown to cleave reduced and S-carboxamidomethylated bovine neurophysin between Cys-13 and Gly-14. The scission resulted in formation of two separable fragments: a smaller peptide arising from residues 1 through 13, and a larger peptide comprising the remainder of the residues of the protein. By dansylation procedures, the smaller peptide was shown to have amino-terminal alanine as expected from the sequence of neurophysin II, and the larger peptide had amino-terminal glycine as anticipated. These results show that collagenase indeed cleaves bovine neurophysin II in accord with the specificity postulated for that enzyme, i.e., scission between -X-Gly- in a sequence of -Pro-X-Gly-Pro-Y-. This result, obtained with a non-collagenous protein substrate, is further confirmation of the specificity of collagenase as established by its action on collagens and on synthetic oligopeptides.
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PMID:Specific cleavage of reduced and S-carboxamidomethylated neurophysin II by the collagenase of Clostridium histolyticum. 20 39

Peptide inhibitors of angiotensin I-converting enzyme (peptidyldipeptide hydrolase, EC 3.4.15.1) were produced by digesting gelatin with bacterial collagenase. The inhibitors were isolated from the digests with a combination of alcohol fractionation, treatment with Amberlite CG-50 column, gel filtration through Sephadex G-25, and Dowex 50 column and paper chromatography. Nine peptide fractions were purified to apparent homogeneity judging by thin-layer and ion-exchange column chromatography, and amino acid composition. Amino acid sequences of the peptides were determined: 2 were found to be mixtures of peptides and the sequence of another was only partially determined. Six of the peptides were potent inhibitors of the converting enzyme, while the other three were less active. 6 peptides were substrates for the enzyme. The enzyme released a dipeptide, Ala-Hyp from one peptide and was strongly inhibited by this dipeptide. The remainder of the parent peptides was a less effective inhibitor.
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PMID:Peptide inhibitors of angiotensin I-converting enzyme in digests of gelatin by bacterial collagenase. 21 31

Techniques are descirbed for the isolation and culture of endothelial cells from the lungs of small animals. The cells are collected by retrograde perfusion of blood-free lungs with buffered saline containing collagenase. The cells are characterized by light microscopy, electron microscopy of thin sections and surface replicas, and by the presence of angiotensin-converting enzyme (ACE). ACE was assayed using 3H-benzoyl-Phe-Ala-Pro as substrate and was localized by indirect immunofluorescence using guinea pig endothelial cells incubated with rabbit antibodies to guinea pig lung ACE followed by goat anti-rabbit globulins conjugated to fluorescein. Thus, endothelial cultures can be established using small animals commonly employed in studies of pulmonary processing of vasoactive substances.
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PMID:Isolation and culture of endothelial cells from the lungs of small animals. 22 81

The synthesis of collagenase in Acinetobacter sp. was found to be inducible by denatured collagen and by its high molecular weight fragments. The presence in the inducer of part of the tertiary structure appear to be indispensable. On the other hand, an addition of Casamino acids, meat protein hydrolysate, or a mixture of amino acids with a similar composition to gelatin does not stimulate collagenase synthesis. Enzyme production was severely repressed in the early phase of growth by glucose, arabinose, and ribose, single amino acids, proline, hydroxyproline, alanine, glutamic acid or casein acid hydrolysate. A mechanism of repression similar to catabolite repression was involved in the phenomenon caused by carbohydrates. However, the fact that cyclic adenosine 3'5-monophosphate did not overcome the repression caused by amino acids or Casamino acids, in contrast to classical catabolite repression, suggests that these two forms of repression may be distinct.
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PMID:[Induction and repression of the collagenase synthesis in Acinetobacter sp]. 22 95

1. The synthetic peptide, 2,4-dinitrophenyl-L-Pro-L-Leu-Gly-L-Ile-L-Ala-Gly-L-Arg-amide (DNP-peptide) was tested as a potential substrate for uterine collagenase. Rat uteri were homogenized and the insoluble fraction was extracted at 60 degrees C to obtain collagenase. The extracts were chromatographed on Sephadex G-150 to yield two peaks of DNP-peptide hydrolyzing activity. Peak I was completely inhibited by EDTA and had a molecular weight greater than 100 000. Peak II was inhibited about 90% by EDTA and had an apparent molecular weight of about 70 000. 2. Peak II coincided closely, but not exactly, with the peak of collagenase activity. It differed from collagenase in heat stability, binding properties on CM-Sephadex and failure to display latency. 3. Peak II represents a new endopeptidase activity. It has a pH optimum of 7 and it cleaves the DNP-peptide at the Gly-Ile and, possibly, the Leu-Gly bond. 4. The DNP-peptide is not a satisfactory substrate for the assay of impure collagenase preparations nor does it inhibit the action of collagenase on collagen substrate when added in 30-fold molar excess.
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PMID:Separation of collagenase and a metal-dependent endopeptidase of rat uterus that hydrolyzes a heptapeptide related to collagen. 22 33

An insoluble preparation of rat dentin matrix was shown to possess bone morphogenetic protein (BMP) activity, i.e. the capacity to induce the formation of catilage and bone when implanted intramuscularly. Since BMP activity was previously attributed to noncollagenous proteins (NCP) of bone and dentin, the nature of NCP of the rat dentin was examined. After treatment of the matrix with purified bacterial collagenase, three NCP were solubilized concomitantly with digestion of the dentin collagen to smaller peptides. The three proteins were separated by anion-exchange chromatography on DEAE-cellulose. Two of the NCP were rich in asparate, glutamate, glycine, serine, and alanine, and thus displayed compositions similar to acidic proteins of other connective tissues. The third NCP was shown by amino acid composition to be the aspartate, serine-rich phosphoprotein, which occurs mostly in a soluble form in rat dentin. This observation supports the view that a portion of dentin phosphotprotein is firmly bound.
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PMID:Noncollagenous proteins of a rat dentin matrix possessing bone morphogenetic activity. 26 54

Renal gluconeogenesis was studied in suspended tubule fragments isolated by collagenase treatment of rat kidney cortices. Angiotensin II increased glucose formation from pyruvate, lactate, and to a lesser extent from oxoglutarate and glutamine, but not from other substrates such as malate, succinate, dihydroxyacetone or fructose. Stimulation was significant with peptide concentration exceeding 1 . 10(-8) M and was also shown with an 8-Sar derivative. Other peptides such as 4-Ala-8-Ile-angiotensin II, hexapeptide and bradykinin had no effect. The stimulatory action of angiotensin II was additive to that of L-lysine, and 3',5'-adenosine cyclic monophosphate, suggesting a different mechanism of action. In the presence of maximally stimulatory concentrations of oleate, phenylephrine and 3',5'-guanosine cyclic monophosphate, however, the stimulatory effect of angiotensin II was absent. Cyclic GMP levels, however, did not increase in tubules after angiotensin II and phenylephrine addition, making a messenger function of this nucleotide unlikely. Omission of Ca2+ from the medium markedly reduced basal gluconeogenesis but did not result in a complete loss of angiotensin II effect. Reduction of medium potassium to 2 mM, however, increased basal gluconeogenesis and blunted the peptide effect. 1 mM ouabain was also able to inhibit the stimulatory effect of angiotensin II. Therefore changes in intracellular potassium levels are discussed as a possible mechanism of angiontensin action, whereas calcium seems not to be specifically linked to this metabolic action of angiotensin on the proximal tubule.
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PMID:Stimulation of renal gluconeogenesis by angiotensin II. 45 78

A chromatographic method is developed for quantitative estimation of the collagenase-like enzyme (CLE) activity in extract of adenohypophysis and in preparations obtained during various steps of the enzyme isolation. The enzymatic hydrolysis of Cbz-Gly-Pro-Ala-Gly-Pro-Gly-OCH3 in presence of 2-mercaptoethanol at pH 8.0 was used as a pattern. The products formed were separated by chromatography on the paper; then they were stained with ninhydrin and converted into cupric complexes during extraction with ethanol; the optic density was measured at 510 nm. The optimal conditions for the enzymatic reaction were established. The method enabled to estimate the CLE activity in presence of prolyl carboxypeptidase. The specific effect of the CLE purified preparation on various synthetic peptides is discussed.
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PMID:[Chromatographic method of determining the activity of the collagenase-like enzyme of the adenohypophysis and several findings concerning the specificity of its action]. 88 63

1. Isolated lamb liver cells were prepared from 24-h-starved animals by venous perfusion of the excised caudate lobe with buffer containing collagenase. On the basis of Trypan-Blue exclusion, rate of O2 uptake, adenine nucleotide content and retention of constitutive enzymes, these cells were judged to be intact. 2. Isolated caudate-lobe liver cells showed rates of gluconeogenesis from 10 mM-propionate and 10 mM-lactate that compared favourably with rates determined in isolated median-lobe cells and with rates determined with the isolated perfused lamb liver. 3. The gluconeogenic potential of substrates tested depended on the lamb's age. Cells prepared from suckling lambs (up to 20 days of age and essentially non-ruminant) showed highest rates from galactose, serine and alanine; those prepared from post-weaned lambs (older than 30 days of age and ruminant) showed highest rates from propionate, lactate and fructose. 4. Gluconeogenic rates from endogeneous precursors, 10 mM-propionate and 10mM-galactose, were linear for 1 h and were both stimulated by 1 muM-glucagon. Provided the endogenous rate of gluconeogenesis remained unchanged after substrate addition, glucagon caused a net stimulation of gluconeogenesis from each of these substrates. 5. Gluconeogenic capacity and glucagon sensitivity were examined in cells maintained in substrate-free oxygenated buffer at 37 degrees, 22 degrees and * degrees C. Even under the best of the three conditions of storage that were tested (i.e. at 22 degrees C in gelatin-containing buffer) deterioration of the lamb cells proceeded rapidly, and loss of glucagon responsiveness preceeded the loss of ability to convert precursor into glucose. 6. n-Butyric acid, 2-methylpropanoic acid and 3-methylbutanoic acid at concentrations comparable with those found in lamb portal-vein blood each stimulated gluconeogenesis from 10mM-galactose or 10mM-propionate; gluconeogenesis from galactose was stimulated to the greater extent. 7. The regulatory effects of glucagon and sodium butyrate on lamb liver-cell gluconeogenesis and glycogenolysis were compared. Glucagon (1 muM) and 2mM-butyrate accelerated the rate of glucose formation of liver cells of 24h-starved animals from lactate+pyruvate or fructose. Insulin (20nM) decreased both gluconeogenesis and the efficacy of 1 muM-glucagon. For lactate+pyruvate as substrate, the stimulatory effect of butyrate was additive to that of 1muM-glucagon and for both lactate+pyruvate and fructose the stimulatory effect of butyrate was not influenced by 20nM-insulin. In contrast with glucagon, which stimulated the rate of glycogenolysis in cells prepared from fed lambs, butyrate (0.1-20mM) had no effect. 8. It is concluded that glucagon and butyrate stimulate lamb liver-cell gluconeogenesis by different mechanisms.
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PMID:Gluconeogenesis in isolated intact lamb liver cells. Effects of glucagon and butyrate. 94 49

By perfusion of the isolated human liver with collagenase and hyaluronidase a mixed suspension of various cell types was obtained. Pure parenchymal cells were prepared by differential centrifugation, pure non-parenchymal cells by the use of pronase and subsequent isopycnic centrifugation on metrizamide gradients (50-300 g/l). About 90% of the parenchymal and non-parenchymal cells were viable as judged by trypan blue staining. Non-parenchymal cells were not capable fo gluconeogenesis but at high rates. Parenchymal cells retained their ability to form glucose and to accumulate glycogen from fructose greater than lactate/pyruvate greater than alanine. Studies on binding of 125I-labelled insulin by isolated parenchymal cells were performed at 30 degrees C. The binding data may fit with a minimum of two classes of binding sites: (a) high affinity--low capacity sties (Kd approximately 6.6 nmol/l, capacity approximately 16 000 insulin molecules per cell) and (b) low affinity-high capacity sites (Kd approsimately 0.37 mumol/l, capacity approximately 646 000 molecules per cell).
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PMID:Preparation of parenchymal and non-parenchymal cells from adult human liver--morphological and biochemical characteristics. 100 13


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